于桥水库富营养化评价及空间分布特征研究

基于天津市于桥水库2000-2010年水质数据,结合卡尔森富营养化指数与3种GIS空间插值方法(反距离权重、径向基函数、普通克里金),评价水库富营养化状态并对其空间分布特征及成因进行分析。结果表明:①普通克里金插值方法下的指数半方差模型插值精度较高。②水库富营养化主要表现为氮污染超标,有机污染较轻,磷为限制因子,在降雨集中的汛期(7-9月)水质营养状态空间差异显著。③水库整体水质呈中营养-轻富营养状态,范围为45.87~54.58,水库北岸由于沿岸畜禽养殖污染已处于轻富营养状态,南岸由于农业产生的面源污染呈现向富营养化转变的趋势,反映了水库富营养化空间分布状况,为建立有效的水库环境保护措施提供了新思路。

Evaluation and spatial characteristics of eutrophication in Yuqiao reservoir

Three different methods of GIS spatial interpolation and Carlson eutrophication index were applied to analyze the status and spatial distribution characteristics of eutrophication and environmental factors in Yuqiao reservoir over past 11 years. The results showed that exponential semi-variogram model of OK was the best interpolation method compared through the result of cross-validation; eutrophication of Yuqiao reservoir was mainly contributed by excessive nitrogen loading, less influenced by organic pollution, limited by phosphorus, and the spatial difference of nutrients for the reservoir was significant during flood season; eutrophication status of Yuqiao reservoir is between nutrient and mesotropher and its value is from 45.87 to 54.58, the north shore of reservoir has been in mesotropher because of livestock and poultry farming pollution and the south shore of the reservoir has become mesotropher water and tend to be of eutrophication because of agricultural non-point pollution. The results reflect the spatial characteristics of eutrophication and provide a new guideline to establish effective environmental management measures for the protection of Yuqiao reservoir.